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Assassin (アサシン, Asashin?) is an Assassin-class Servant summoned by Ritsuka Fujimaru in the Grand Orders of Fate/Grand Order.



« The Artoria Species is like a cancer of the universe.
Someone must reap them out.
Someone must. »

(Mysterious Heroine X)
Assassin's True Name is Mysterious Heroine X (謎のヒロインX, Nazo no Hiroin?), also known as Heroine X (ヒロインX, Hiroin X?) and just X, an unknown heroine who tasked herself in eliminating Saber-class heroines during Back Alley Satsuki - Chapter Heroine Sanctuary. Bearing the code name "A-X", X was a stranger who came from the "mysterious dimension" called the Servant Universe. Seeking to accomplish her "true, dearest wish" to "defeat all Sabers", she brandished Secret-Calibur and left her home town, leaving behind an "expression full of bitterness."[2]

Even before arriving at Chaldea, she managed to save an ancient royal dynasty from a crisis, settle the internal strife of the "Mankind Integration Union", and rout invaders from another universe, but such actions were trivial enough for her to not even remember accomplishing them. She will continue to brandish her sword until her goal is completed, and can still be seen "dashing across the sea of stars" even today. No matter what, she also plans to cut down the "Golden Great Emperor Cosmo Gilgamesh."[2]

X has revealed to none that her true identity is actually Artoria Pendragon. While she believes that her "perfect disguise" has tricked everyone, it is asked that others keep the fact quiet to keep from spoiling it and also for the sake of X's own honor.[2]


« It's sticking's sticking's really sticking out. »

(Assassin's profile, on her ahoge)
Assassin's appearance is said to be of a young woman with "rough and sporty garments unseemly for Servants." Her blue muffler is a symbol of courage, and her cap is used to hide her identity and ahoge, although it sticks out of the cap.[2]


  • Annihilation List (殲滅リスト, Senmetsu Risuto?)

Although Assassin displays a "carnage mode" wagering her single holy sword on nothing but defeating all present Sabers.[2]

Mystery Heroine X's wish for the Holy Grail is the destruction of all other sabers. Or at least for them to change their class name to Attacker or Swordsman or something.


Saber Class
Artoria Lily
she opened her heart towards Saber Lily alone.[2]
Mysterious Sailor X


Fate/Grand OrderEdit

SABER WARS – Lily’s Cosmic Training – The Caliburn AwakensEdit

X crash lands into the Singularity that Ritsuka and Mash are using to help train Artoria Lily when her ship, he Du Stallion II, is crashed by Ultra Heroine Z. She emerges from ship, and tells Artoria that her attitude is pathetic and fainthearted. She then fights her to show her what a true Saber is. After the group defeat her, X compares to their fight to a warm-up exercise, and compares the group to preschoolers. However, they note her struggling during their fight, which X attributes to her holding back. She introduces herself, and claim herself to be the Saber of Sabers to Artoria and Mash's amazement.She then decides to take Artoria as her student due to her being unable to overlook her. After being accepted as her teach, X tells Artoria she needs three kinds of materials possessing mysterious powers spread across the world in order to repair her ship. After Artoria accepts the task, X tells her and the others that they must defend the ship from monsters and collect Artorium particles from them, which she'll use to power up Artoria. Accepting X as her teacher, Artoria is told by X that she must three kinds of materials possessing mysterious powers spread across the world in order to repair X's ship, the Du Stallion II.

After the group defeats some monsters attacking the ship, X explains Artorium is used to power her ship and its Spirit Origin Enhancement Device, Adam Kadmon, which will be used to physically enhance Artoria Lily. Blackbeard then suddenly appears along with a rather silent Gilles de Rais in order to both take X's ship parts and to take either Artoria Lily or Mash as his wife. After the group manages to defeat him, Blackbeard is tied up and compliments X's sword, which Artoria Lily agrees with. Artoria agrees to let Blackbeard train her despite the protests of X and the other. However, the training is cut short after he is struck twice in the crotch by Caliburn thanks to her lack of aiming.

The next day, X mistakes Artoria asking about her origins as her having an ulterior motive. She decides to tell it though when Artoria explains she wanted to make a popular dish from X's hometown as thanks for helping her. X explains that she is both from the future and the Servant Universe, and she came to the present in order to save the future. She then instinctively attacks Nero Claudius when she, along with EMIYA and Tamamo-no-Mae, arrives to investigate her ship. After the group defeat her group, Nero offers to be Artoria's sparring hero, but X protests it. X tries to fight Nero again, but EMIYA stops her. He offers to train Artoria instead, which both she and X accept.

After X quickly defeated ParacelsusOkita SoujiMedeaMedea Lily, and Siegfried when they came for her ship, Artoria Lily questions her actions since she could've reached an understanding with them if she talked with them. The group then decides to ask X about her true intentions when Charles Babbage warns them about X's ship after they defeat him, Sakata Kintoki, and Nikola Tesla. X explains that the reason the future is doomed due to the Saber class's value plummeting due to their overabundance in the future, which has caused an economic crisis in her universe. Now understanding X's reasons for instinctively attacking any Sabers she sees, Artoria Lily wonders if she should be destroyed since she's a cause of the over-saturation of Sabers that X spoke of. But, X explains that she must leave at least one Saber otherwise she wouldn't exist, and believes Artoria Lily to be that one. However, X is suddenly attacked by Ultra Heroine Z, a paradox version of X to kill her after she fulfilled her mission in the past to kill all Sabers. While she is unconscious, the group defeat Z. After she wakes up, X thanks Artoria for saving her. She then admits that she was deceiving her the whole time, but Artoria wishes to continue her training since X believed in her. Taken aback by her innocence and kindness, X decides to postpone her mission to continue Artoria Lily's training. While Artoria is training, X tells Ritsuka that Artoria cannot change Britain's fated destruction. Despite that though, she feels Artoria can at least change the process, with Britain's end being either tragic or tranquil. She then tells Ritsuka that she and Artoria owe a lot to Chaldea, and offers to help them.

Kara no Kyoukai: The Garden of Order Edit

X crashes into the Ogawa Apartment following a highly concentrated Saber signal. In response, Shiki Ryougi changes into her Saber self, who X finds terrifying. She then claims she had the wrong person, and asks to be allowed to go home. But she is forced to fight Shiki when her emergency warps fails. She is defeated but claims it doesn't count unless she loses against a blonde Saber. She then retreats after saying they meet again as friends.

Salomon: The Grand Time Temple Edit

She is amongst the Servants to assist the Chaldea against Demon Gods Pillar.[3]

Musashi Trial QuestEdit

X traps Ritsuka and Miyamoto Musashiinside a Reality Marble with her W.F.D. Bracelet when they arrive at third gate. She ambushes Musashi, but Musashi deflects the projectiles sent out. X shows herself and declares that a true Saber only holds one beloved sword in hand and that the twin sword style is the ultimate way of evil. Musashi acknowledges X's swordsmanship as first-rate, even though it's from a school she's unfamiliar with. The two fight, and while X is struggling, Musashi is able to find her weak point with her Mystic Eye. Musashi then removes the Reality Marble by destroying X's W.F.D. Bracelet. X is angry that Musashi destroyed it since it was made by the engineer who joined her Knights of the Round Table team, Lionhead. She decides to retreat out of fear, but claims Musashi hasn't won yet. She also tells her to watch out for when a second and third of herself arrive. She then disappears after saying goodbye to Ritsuka hoping to see them again.

GUDAGUDA Meiji Restoration Edit

X appears under the name of Mysterious Chousokabe Heroine X as one of the Servants summoned by Andras to serve Oda Nobukatsu. She defends the Sun Fortress against Ritsuka, Okita, Oda Nobunaga, and Hijikata Toshizo while Nobukatsu sacrifices Lady Chacha to Andras. She is defeated by the group along with the others.

GUDAGUDA Strange Tales of the Imperial Holy Grail Edit

X appears under the the name of Mysterious Kasuya X as one of Chacha's Seven Imperial Spears. She is corrected that Okita Alter is an Alter Ego when mistakes her as a Saber, but she decides to hunt her for her face alone. She ends up fight Okada Izou, wondering if he's a Saber due to his impressive swordsmanship. He claims he neither Saber or Assassin, but a Ripper instead. She then helps Ritsuka, Okita Alter, and Sakamoto Ryoma to defeat him, angry at an Assassin imitating a Saber. She also tells Okita Alter to meet at the back of the Sports Warehouse afterwards, for she has something to say about her face.


In her first interlude, Saber Slayer: Dawn (セイバースレイヤー 黎明編, Seibā Sureiyā: Reimei-hen?), X tells Ritsuka and Mash that there is a tournament for the title of Saber of Sabers. She states she cannot stand that Sabers are gathering from all over the world to participate. She is angry she didn't get an invitation, claiming herself to be the greatest of all Sabers. She says she will not allow a tournament that will not admit her to happen. She decides go in anyway to show the others what a real Saber looks like.

Entering the tournament at the third round, X faces off against Mordred, who quickly recognizes the former as her father. X replies she doesn't whose child Mordred is, and fights her. After defeating Mordred, X claims Britain's crisis has been averted, and states another Saber who isn't her is gone. Mash wonders if X met Mordred somewhere, but X adamantly denies Mordred being family.

In her second interlude, Saber Slayer: Clash (セイバースレイヤー 激闘編, Seibā Sureiyā: Gekitō-hen?), X has already defeated countless Sabers in the tournament. Her opponent is Nero, and claims she would be getting more cheers if they were in Britain instead of Rome. Nero proposes a pre-battle song, but X interrupts her and claims she came to stop her tyranny. She addresses her as Red Saber, which causes Nero recognize X's face. X declares she cannot permit red in the Saber lineup since she didn't give her permission. She then fights Nero, and offers to forgive her if she throws her a feast. But Nero refuses, so the fight continues. After she is defeated, Nero finally remembers X's true identity, but X angrily finishes her off when Nero calls her Jeanne d'Arc.

In her third interlude, Saber Slayer: Awakening (セイバースレイヤー 覚醒編, Seibā Sureiyā: Kakusei-hen?), X and the others travel to a castle in Britain to face her final opponent: Artoria Pendragon, whose very confused by her participation. X says she and Artoria are two sides of the coin, and claims she cannot become a true Saber unless she defeats her. She then prepares to fight Artoria, even though she is concerned about causing a space-time collapse. Artoria decides to fight X, declaring she cannot her out into the world for her and others' sake. As the fight continues, Artoria asks X what drives her. X answers that Artoria wouldn't understand the terror of seeing many more of her own face appearing; Romani Archaman says she understands though. The two then empower their holy swords, not wanting lose against the other, and continue their battle. Despite Artoria havng the home field advantage, X is able to defeat her. X is then congratulated by the other Sabers for winning the tournament. However to her utter disappoint, it is revealed the entire thing was a dream.

Other appearancesEdit

She appears as alternate costume of Saber in Fate/EXTELLA.


Assassin claims to be the "definitive edition of the Saber Class", acting as an Anti-Saber Decisive Weapon (対セイバー決戦兵器, Tai-Seibā Kessen Heiki?) that "fairly and squarely performs surprise attacks as a knight." She brandishes the "mysterious magic sword" Secret-Calibur to massacre her enemies and uses her favorite ship, the Dun Stallion II (ドゥ・スタリオンⅡ, Du Sutarion II?), to travel through space.[2]

A Cosmo Reactor (コスモリアクター, Kosumo Riakutā?) allowed only to the multiplying Sabers. It is reacting to various things. Settings, for example.[1]

Her Riding ability. She can't ride every possible ride-able object, but when it comes to managing ordinary spaceships, this skill displays a terrific effect. To the point where she can warp even using a ship with no warp function.[1]

She has a EX rank Presence Concealment, but it is sealed due the user herself completely denying it.[1]

Due to a mysterious communication device, the Dun Stallion can automatically provide Supporting Bombardment (支援砲撃, Shien Hōgeki?). In a one-on-one fight between fellow swordsmen, there are no unexplored territories nor soulful tactics.[1]

Her Instincts are considerably lower than the normal Artoria's, but only when facing a Saber, her instincts rank-up to A.[1]

Galactic Meteor Sword (銀河流星剣, Ginga Ryūsei-ken?) is a power given to Saber that can destroy even stars. Also known as the sword that absolutely kills Sabers. Its attack is super effective against Sabers, so would it be an exaggeration to say that she is the greatest Saber of all?[1]

Forms and Alternate VersionsEdit

Ultra Heroine ZEdit

Ultra Heroine Z (ウルトラヒロインZ, Urutora Hiroin Z?) is an alternate version of Mysterious Heroine X who acts as the antagonist of the "Saber Wars" event. An alternate version of Mysterious Heroine X, created by her events in the past, causing a paradox to kill her after she fulfilled her mission to kill all Sabers and thus, become the most powerful Saber in the past. Ultra Heroine Z is mostly the same as Mysterious Heroine X, but she loathes all Sabers (including Lily and especially Nero) and deems MHX a faillure as a Saber Killer for "opening herself to the enemy".


Creation and ConceptionEdit

She makes her first appearance in 2013 April Fools.

Nasu Kinoko is the scenario writer for Mysterious Heroine X in Fate/Grand Order.[1] Takashi Takeuchi is the character designer for Mysterious Heroine X.[1] BUNBUN is the character illustrator for Assassin.[1][2]


  1. 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 1.12 1.13 1.14 1.15 1.16 1.17 1.18 1.19 1.20 1.21 1.22 1.23 1.24 1.25 1.26 1.27 1.28 1.29
  2. 2.00 2.01 2.02 2.03 2.04 2.05 2.06 2.07 2.08 2.09 2.10 2.11 2.12 2.13 2.14 2.15 2.16 2.17 2.18 2.19 2.20 2.21 2.22 2.23 2.24 2.25 2.26 2.27 2.28 Fate/Grand Order - Mysterious Heroine X Profile, Translated by Master of Chaos.
  3. Fate/Grand Order - Salomon: The Grand Time Temple - Act 09: X / Disposal Chute Andromalius
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